A computer keyboard is the main input device for computers, and it uses an arrangement of keypads that can serve a variety of different functions. There are mechanical keyboard and membrane keyboard in the market. The mechanical keyboard has tactile switches that have a noticeable actuation point so that user can hear a “click” when the keypad is pressed. However, the sealing strength of the mechanical keyboard is lower than the membrane keyboard, so the mechanical keyboard has higher chance to let dust or wet air to go inside, result in failure. On the other hand, the mechanical keyboard is much compact in structure so that it can provide good sealing strength, such that it is capable of providing dust-proof and moisture-proof effects. Accordingly, developers are constantly trying to develop a new keypad that has advantages of both the mechanical keyboard and the membrane keyboard.